Project Summary Posttraumatic stress disorder (PTSD) resulting from intimate partner violence (IPV) is a common experience among women?one that has been linked to dysfunctional parenting behaviors. Despite the prevalence of IPV- related PTSD and its impact on parenting, little is known about the mechanisms responsible for this association. The present project addresses this gap by examining the impact of IPV-related PTSD on dysfunctional parenting behaviors in a laboratory setting. Based on prior theory and empirical evidence, it is expected that a diagnosis of PTSD will be associated with more dysfunctional parenting (i.e., harsh/overreactive and lax/permissive behaviors) during routine mother-child discipline encounters. Further, drawing on prior research linking negative emotion and greater dysregulated cortisol reactivity (i.e., high or dampened) to both PTSD and dysfunctional parenting, we expect that experienced emotion and cortisol reactivity will fully mediate the relationship between PTSD status and dysfunctional parenting behaviors. To test these hypotheses, mothers and their 18- to 42-month-old children will complete a laboratory paradigm designed to elicit typical discipline encounters occurring with young children. Shortly thereafter, mothers will view a video of the interaction and provide in-the-moment ratings of their experienced emotions. Salivary cortisol will be collected from mothers prior and subsequent to the lab paradigm to assess stress-related cortisol reactivity. Knowledge gained from this study is expected to improve intervention and prevention efforts for mothers with IPV-related PTSD and their families by informing researchers and practitioners about the processes by which PTSD impacts parenting behaviors.